Sometimes, pools or spas that are using brominating products as their sanitiser may appear to have a clear green or yellowish cast in the water. This is usually caused by a high total bromine residual and a low pH.

To eliminate the discolouration:

Test for copper to ensure the problem is not due to oxidised copper. If copper is present, treat with Pool Magnet and Quick Clear according to label instructions.

If there is no copper, test the bromine and pH level. When testing the pH with the Wet Lab, use up to 5 drops of Chlorine Neutraliser to ensure an accurate pH reading. Brominating compounds can sometimes discolour the pH test ("bromophenol blue"). Adjust the pH if it is low and turn off the brominator or stop the source of bromination until the total bromine residual comes down to 6.0 ppm.

Once the total bromine residual has dropped, turn the brominator back on or resume your normal bromination method. Adjust the flow rate on the brominator or your feed rate to decrease the amount of brominating product being introduced into the water.